Often applied in process automation technology are field devices to serve for registering and/or influencing process variables. Thus, sensors, such as, for example, fill-level measuring devices, flow measuring devices, pressure- and temperature-measuring devices, pH-redox potential measuring devices, conductivity measuring devices, register corresponding process variables, fill-level, flow (e.g. flow rate), pressure, temperature, pH-value, and conductivity, respectively, while actuators, such as, for example, valves or pumps, serve for influencing process variables, such as, for example, changing the flow of a liquid in a section of pipeline, or the fill-level in a container.
Referred to as field devices are, in principle, all devices placed near a process for delivering or processing process-relevant information. A large number of such field devices are manufactured and sold by the firm, Endress+Hauser.
In modern industrial plants, field devices are, as a rule, connected via bus systems (Profibus®, Foundation® Fieldbus, etc.) with one or more superordinated units. Instead of a bus system, also, for example, a parallel-wire or an analog signal transmission can be provided between the field devices and the one or more superordinated units. Normally, the superordinated units are control systems, or control units, such as, for example, a PLC (programmable logic controller) or PCS (process control system). The superordinated units serve for, among other purposes, process control, process visualization, process monitoring, as well as for start-up of the field devices.
For minimizing down-time of a plant containing field devices, modern industrial plants frequently employ computer-supported, upkeep systems, which manage, in a database, upkeep-relevant information regarding the field devices and, on occasion, also other devices being used in the plant. These systems are referred to herein as “computer-supported, upkeep systems”. These, as a rule, software-based, computer-supported, upkeep systems can, depending on supplier and on configuration of the plant of interest, perform various functions with reference to the management and organization of upkeep work. Especially, these computer-supported, upkeep systems can perform the procedures and functions conventionally manually performed by maintenance personnel or a management person responsible for upkeep of the plant, in order to plan upkeep work to be done and to document performed upkeep work.
A software-based, computer-supported, upkeep system of this type is known under the acronym “CMMS” (computerized maintenance management system). As a rule, at least the following functions are provided by a CMMS, with it being understood that deviations can arise in the case of particular CMMS versions offered by individual suppliers:
Creating and planning upkeep jobs for individual field devices (and, on occasion, other devices of a plant), based on device-specific upkeep intervals and data on already executed upkeep work, as well as, on occasion, additionally based on information concerning available maintenance personnel;
recording and documenting of service reports, malfunction reports, inputs regarding required replacement parts and/or of work orders regarding other upkeep work to be done;
asset management, especially managing and providing of device data, handbooks, check lists, warranty information, upkeep intervals, service contracts, information concerning purchase date, information concerning service life to be expected, replacement part information, information concerning malfunction reports of the field device and for problem handling of the same and/or information concerning parametering, calibration and/or configuration of the individual field devices (and, on occasion, other devices of a plant);
inventory management, especially management of inventory quantities and execution of queries concerning the availability of replacement parts, tools, aids and consumed materials sent to a storage location (for example, a storage location of the plant operator) or to a manufacturer;
statistical analysis, especially providing information regarding frequency of various defects or malfunctions, number of already executed upkeep jobs, maintenance costs, etc., in the case of the different field devices (and, on occasion, in the case of other devices of a plant).
Alternatively to, or in supplementation of, a CMMS, also a “PAM” (plant asset management) can be provided. In a PAM-system, as a rule, various relevant pieces of information and their time sequence are stored for the individual field devices (and, on occasion, for the other devices of a plant). Especially, documented in a PAM are device-specific data, starting from the date of manufacture right up to the current date, such as, for example, information concerning performed upkeep work, exchanged parts, etc. Besides CMMS and PAM, other software-based, computer-supported, upkeep systems exist, these being “manufacturer-specific, computer-supported, upkeep systems”, by which upkeep-relevant information of one or more field devices are managed in a database. These other maintenance systems perform, as a rule, at least a part of the functions explained above in reference to CMMS and PAM.
Computer-supported, upkeep systems of such type are frequently employed in a plant-encompassing manner, in order, for example, to manage upkeep-relevant information of field devices and, on occasion, of other devices connected in a plant, for all plants of a plant operator. Frequently, the computer of the data processing installation, in which such a computer-supported, upkeep system is implemented, is arranged spatially separated from the individual field devices (and, on occasion, from further devices of the plant). Maintenance personnel performing upkeep work on-site at a field device, cannot, therefore, directly access information stored in the computer-supported, upkeep system. Additionally, the computer-supported, upkeep system cannot be directly updated by the maintenance personnel.
In order to have the information relevant for the upkeep of a field device available on-site, it has been usual, to this point in time, for the maintenance personnel or a third party to retrieve the presumably required information in advance from the computer-supported, upkeep system. For this, it has been necessary that the pertinent person visit the computer or the data processing installation, where the computer-supported, upkeep system is implemented, or, on occasion, another computer, which can access the computer-supported, upkeep system via a company network, and print out the presumably required information in paper form or transfer such information via an appropriate interface (e.g. USB, Bluetooth or infrared) onto a “PDA” (“Personal Digital Assistant”). To the extent that the computer or the data processing installation, where the computer-supported, upkeep system is implemented, is Internet connected, there is, additionally, the option that such person can download the presumably required information via the Internet in advance via a computer with stationary Internet access (e.g. via a cable modem). The downloaded information could then be saved on the computer, which is, as a rule, at the workplace of the affected person, and additionally printed out in paper form and/or transferred onto a PDA. The printouts in paper form and/or the PDA with the information saved in advance can then be taken with the maintenance personnel to the field device.
It is, however, often not possible to correctly predict in advance exactly that information which will be needed. Therefore, as a rule, more extensive information is obtained than will eventually actually be necessary. Additionally, an added time and management effort is connected with obtaining this more extensive information. Furthermore, the case can arise, in which the maintenance personnel determine, on-site, that the information brought along in the PDA and/or in paper form is not sufficient and further information must be obtained from the computer-supported, upkeep system. The required maintenance tasks can then not be performed immediately, and a new schedule must be arranged. Additionally, there is, in the case of the practice to this point in time, the danger that the most up-to-date information will not be obtained before every maintenance task to be performed, but, instead, the already present information will be used, as stored in the PDA or printed out in paper form. This can, however, already be outdated. After performing the upkeep work, relevant information, such as, for example, a service report, information regarding required replacement parts, etc. must be input into the computer or the data processing installation, where the computer-supported, upkeep system is implemented. For this, in turn, the same opportunities of access are available, which were already mentioned above in reference to the obtaining of the presumably required information. Also this subsequent inputting of data involves a considerable amount of time.